The invention concerns a shelving framework system for making up shelving units, desks and display units for fitting out shops, stores and the like.
One known form of framework system includes a support provided with any suitable form of base on which is disposed an upright over which is threaded a sleeve made up of several sections, with reduced diameter portions at the ends, and cross-braces threaded on back-to-back. The cross-braces have a cylindrical body complementing the uprights and a conical flared portion with the larger cross-section at the free end. The sleeve sections are provided with reduced diameter portions near their ends providing abutments for the larger ends of the conical flared portions and thus limiting the penetration of the cross-braces into the sleeve sections.
Another known form of upright has virtually the same features, namely a base at its lower end, sections making up a covering sleeve, cross-braces threaded on back-to-back, and clamping screws, but the uprights, cross-braces and sleeve sections have flat faces acting as a brake and preventing rotation in the vertical plane of the various accessories hooked onto the upper edges of the sleeve sections.
Such systems are relatively expensive, however, as a large number of basic elements are required. Also, the various elements must be carefully selected, which involves wasted time when assembling the system.
To remedy these disadvantages, supports have been designed which consist of hollow tubes with polygonal cross-sections and with horizontal bores at regular intervals in which are inserted the means for hanging and holding the various accessories. These bores can, of course, be formed in one or in all the faces of the polygonal hollow tubes.
A further known form of support is made up of sections with part-conical tips provided with threaded portions. These threaded parts are screwed into threaded holes formed in part-conical openings which adjoin circular recesses in which are inserted the means for attaching the accessories. These supports have various disadvantages. For one thing, they are very expensive, due to the number of machining operations required, including machining the part-conical tips, threading, boring and threading, and machining the part-conical openings. The support is also rather unstable and is easily deformed, especially when the component parts are made of plastics materials. The connection between the tip and the opening is small in height, and the progressive threading of the part-conical tip involves a risk of breaking it. Should this happen, it is necessary to replace two sections, that in which the broken off tip is threaded, and that from which it broke off.